• 한국작물학회지
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• 제35권3호
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• pp.233-238
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• 1990

국내에서 수집된 잡초형 벼 7계통을 Japonica, Javanica 및 Indica 검정종으로 교잡하여 잡종(F$_1$)의 종자임성을 가지고 그들의 재배종과의 친화성을 검토하였다. 그 결과를 요약하면 다음과 같다. 1. 검정종으로 사용된 Japonica, Javanica 및 Indica에 속하는 품종군간의 잡종임성은 각 생태형간의 전형적인 관계를 나타내는 조합도 있었지만 생태형내에서의 분화를 인정할 수 있는 조합도 있었다. 수원조, M. Sinaguing 및 wx817 품종간 조합은 각각 Japonica, Javanica, Indica형간 조합의 곡형적인 것이고 기타 품종들의 조합에서는 각 생태형군내의 분화를 인정할 수 있는 것들이었다. 2. 공시 잡초형 계통들과 검정종들과의 잡종임성은 Japonica와는 반불임내지 완전임성에 가까운 변이를 보였지만 Javanica나 Indica와는 심한 불임을 나타내어 잡초형 계통들이 Japonica에 근록인 것 같이 나타났다. Japonica와의 조합에서 반불임을 보인 출청액미 B나 삼산면 8은 Javanica나 Indica 검정종과의 조합에서 심한 불임을 나타내어 이들이 Indica나 Javanica와 근록인 것 같지는 않았다. 3. 잡초형계통 상호간의 잡종임성은 조합별로는 최저 69%, 최고 96%로 계통평균으로는 75%에서 92%에 달하여 비교적 높은 편이었다. Japonica 검정종과의 잡종에서 반불임을 보였던 2계통은 잡초형계통 상호간 조합평균임성이 1, 2위로 높았다. 4. 잡초형계통들의 Amylose함량, A.D.V.phenol 반응 및 립형은 매우 다양하며, Japonica 검정종과의 잡종친화성도 다양하지만 Javanica나 Indica보다는 Japonica에 유록이 더 가깝지만 Indica 혈통의 영향도 부정할 수 없을 것 같다.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.58-66
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• 2007

Isolation, expression, and characterization of a novel $endo-{\beta}-1,3(4)-D-glucanase$ with high specific activity and homology to Bacillus lichenases is described. One clone was screened from a genomic library of Paenibacillus sp. F-40, using lichenan-containing plates. The nucleotide sequence of the clone contains an ORF consisting of 717 nucleotides, encoding a ${\beta}-glucanase$ protein of 238 amino acids and 26 residues of a putative signal peptide at its N-terminus. The amino acid sequence showed the highest similarity of 87% to other ${\beta}-1,3-1,4-glucanases$ of Bacillus. The gene fragment Bg1 containing the mature glucanase protein was expressed in Pichia pastoris at high expression level in a 3-1 high-cell-density fermenter. The purified recombinant enzyme Bg1 showed activity against barley ${\beta}-glucan$, lichenan, and laminarin. The gene encodes an $endo-{\beta}-1,3(4)-D-glucanase$ (E. C. 3.2.1.6). When lichenan was used as substrate, the optimal pH was 6.5, and the optimal temperature was $60^{\circ}C$. The $K_m,\;V_{max},\;and\;k_{cat}$ values for lichenan are 2.96mg/ml, $6,951{\mu}mol/min{\cdot}mg,\;and\;3,131s^{-1}$, respectively. For barley ${\beta}-glucan$ the values are 3.73mg/ml, $8,939{\mu}mol/min{\cdot}mg,\;and\;4,026s^{-1}$, respectively. The recombinant Bg1 had resistance to pepsin and trypsin. Other features of recombinant Bg1 including temperature and pH stability, and sensitivity to some metal ions and chemical reagents were also characterized.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2219-2225
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• 2015

SHP1 negatively regulates the Janus kinase 2/signal transducer and activator of transcription (JAK2/STAT) signaling pathway, which is constitutively activated in myeloproliferative neoplasms (MPNs) and leukemia. Promoter hypermethylation resulting in epigenetic inactivation of SHP1 has been reported in myelomas, leukemias and other cancers. However, whether SHP1 hypermethylation occurs in MPNs, especially in Chinese patients, has remained unclear. Here, we report that aberrant hypermethylation of SHP1 was observed in several leukemic cell lines and bone marrow mononuclear cells from MPN patients. About 51 of 118 (43.2%) MPN patients including 23 of 50 (46%) polycythaemia vera patients, 20 of 50 (40%) essential thrombocythaemia and 8 of 18 (44.4%) idiopathic myelofibrosis showed hypermethylation by methylation-specific polymerase chain reaction. However, SHP1 methylation was not measured in 20 healthy volunteers. Hypermethylation of SHP1 was found in MPN patients with both positive (34/81, 42%) and negative (17/37, 45.9%) JAK2V617F mutation. The levels of SHP1 mRNA were significantly lower in hypermethylated samples than unmethylated samples, suggesting SHP1 may be epigenetically inactivated in MPN patients. Furthermore, treatment with 5-aza-2'-deoxycytidine (AZA) in K562 cells showing hypermethylation of SHP1 led to progressive demethylation of SHP1, with consequently increased reexpression of SHP1. Meanwhile, phosphorylated JAK2 and STAT3 were progressively reduced. Finally, AZA increased the expression of SHP1 in primary MPN cells with hypermethylation of SHP1. Therefore, our data suggest that epigenetic inactivation of SHP1 contributes to the constitutive activation of JAK2/STAT signaling. Restoration of SHP1 expression by AZA may contribute to clinical treatment for MPN patients.

• 대한치과기공학회지
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• 제36권3호
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• pp.141-147
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• 2014

Purpose: Dental casting #Gr I (Co-25Cr-5Mo-3Sn-1Mn-1Si), #Gr II (Co-25Cr-5Mo-5Cu-1Mn -1Si) and #Gr III (Co-25Cr-5Mo-3Sn-5Cu-1Mn-1Si) master alloys of granule type were manufactured the same as manufacturing processes for dental casting Ni-Cr and Co-Cr-Mo based alloys of ingot type. These alloys were analyzed melting processes with heating time of high frequency induction centrifugal casting machine using infrared thermal image analyzer. Methods: These alloys were manufactured such as; alloy design, the first master alloy manufatured using vacuum arc casting machine, melting metal setting in crucible, melting in VIM, pouring in the mold of bar type, cutting the gate and runner bar and polishing. These alloys were put about 30g/charge in the ceramic crucible of high frequency induction centrifugal casting machine and heat, Infrared thermal image analyzer indicated alloys in the crucible were set and operated. Results: The melting temperatures of these alloys measuring infrared thermal image analyzer were decreased in comparison with remanium$^{(R)}$ GM 800+, vera PDI$^{TM}$, Biosil$^{(R)}$ f, WISIL$^{(R)}$ M type V, Ticonium 2000 alloys of ingot type and vera PDS$^{TM}$(Aabadent, USA), Regalloy alloys of shot type. Conclusion: Co-Cr-Mo based alloy in addition to Sn(#Gr I alloy) were decreased the melting temperature with heating time of high frequency induction centrifugal casting machine using infrared thermal image analyzer.

• Journal of Korean Dental Science
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• 제10권1호
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• pp.10-21
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• 2017

Purpose: The purpose of this study was to investigate the electrochemical characteristics of nanotubular Ti-25Nb-xZr ternary alloys for dental implant materials. Materials and Methods: Ti-25Nb-xZr alloys with different Zr contents (0, 3, 7, and 15 wt.%) were manufactured using commercially pure titanium (CP-Ti), niobium (Nb), and zirconium (Zr) (99.95 wt.% purity). The alloys were prepared by arc melting in argon (Ar) atmosphere. The Ti-25Nb-xZr alloys were homogenized in Ar atmosphere at $1,000^{\circ}C$ for 12 hours followed by quenching into ice water. The microstructure of the Ti-25Nb-xZr alloys was examined by a field emission scanning electron microscope. The phases in the alloys were identified by an X-ray diffractometer. The chemical composition of the nanotube-formed surfaces was determined by energy-dispersive X-ray spectroscopy. Self-organized $TiO_2$ was prepared by electrochemical oxidation of the samples in a $1.0M\;H_3PO_4+0.8wt.%$ NaF electrolyte. The anodization potential was 30 V and time was 1 hour by DC supplier. Surface wettability was evaluated for both the metallographically polished and nanotube-formed surfaces using a contact-angle goniometer. The corrosion properties of the specimens were investigated using a 0.9 wt.% aqueous solution of NaCl at $36^{\circ}C{\pm}5^{\circ}C$ using a potentiodynamic polarization test. Result: Needle-like structure of Ti-25Nb-xZr alloys was transform to equiaxed structure as Zr content increased. Nanotube formed on Ti-25Nb-xZr alloys show two sizes of nanotube structure. The diameters of the large tubes decreased and small tubes increased as Zr content increased. The lower contact angles for nanotube formed Ti-25NbxZr alloys surfaces showed compare to non-nanotube formed surface. The corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface showed longer the passive regions compared to non-treatment surface. Conclusion: It is confirmed that corrosion resistance of alloy increased as Zr content increased, and nanotube formed surface has longer passive region compared to without treatment surface.

• 수면정신생리
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• 제18권1호
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• pp.35-39
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• 2011

목 적: 일중선호도는 하루 중 어느 시간대에 각성도가 높고 활기찬 지에 대한 경향으로 아침형-저녁형이라고도 알려져있다. PER3 유전자는 일중선호도에 영향을 주는 것으로 알려져 왔다. 본 연구에서 우리는 젊고 건강한 피험자들에서 환경과 혼란요인들을 통제하고 PER3 유전자 다형성과 일중선호도간에 연관을 연구하였다. 방 법: 연구에 참여한 대상자는 299명의 의과대학생들(남자 299, 여자 191명)이며 평균연령은 22.9세였다. 일중선호도는 13개 문항의 Composite Scale for Morningness (CSM)로 측정하였다. PER3 VNTR(rs57875989)의 유전자형분석은 중합효소연쇄반응법을 사용하여 이루어졌다. 양측검정으로 유의수준은 p<0.05로 하였다. 결 과: 전체 대상자에 대한 CSM 점수는 31.90${\pm}$6.39 (평균${\pm}$표준편차)였다. 남녀간에 CSM 총점에 유의한 차이는 없었다. PER3 5R/5R에서 CSM 점수가 높은 경향을 보였으나, PER3 VNTR(rs57875989) 유전자형과 대립유전자에 따른 CSM 점수의 유의한 차이는 없었다. 결 론: 본 연구는 젊은 건강한 한국인에서 PER3 V- NTR과 일중선호도간의 연관을 입증하지 못했다. 향후 보다 대규모의 피험자들을 대상으로 PER3의 여러 유전자들에 대해 다형성과 일중선호도간의 연관에 대한 연구가 필요할 것으로 생각된다.

• 한국광물학회지
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• 제13권3호
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• pp.121-137
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• 2000

공주군 유구 일대의 화강암질편마암은 온대습윤기후의 지형적 영향에 기인한 산성환경 및 양호한 배수조건에서의 풍화작용으로 두께가 8m인 깊은 saprolite층과 50cm 이상의 두꺼운 토양층을 형성하였다. 풍화단면에서는 흑운모/질석혼합층 광물, 삼팔면체, 할로이사이트, 캐올리나이트, 일라이트, 이팔면체질식, 스백타이트, 깁사이트, 침철석 등의 풍화광물이 확인되었다. 흑운모의 변질은 질석화작용이 미약한 반면에 풍화단면 전반에서 고령토화작용이 매우 현저한 풍화양상을 보여주며, 흑운모-흑운모/질석 혼합층 광물-질석, 흑운모-할로이사이트, 캐올리나이트, 깁사이트 및 흑운모-일 라이트의 풍화과정을 나타낸다. 흑운모의 풍화작용으로 생성된 고령토광물은 주로 할로이사이트이며, 고령토화작용으로 방출된 Fe는 변질된 흑운모 주변에서 침철석을 형성한다 사장석은 용해-침전작용으로 관상의 할로이사이트를 형성한다. 할로이사이트의 산출양상은 사장석의 용해유형에 따라 방향성이 강한 할로이사이트 집합체와 매우 구불구불한 할로이사이트 집합체로 나타난다. 모암에서 철을 함유하고 있던 광물은 용해되어 모암광물의 가상을 유지한 채 또는 그 주변에서 침철석을 형성한다. 연구지역 화강암질편마암의 단면은 풍화도가 증가할수록 모암 구성광물이 감소하는 반면에 점토광물의 양이 증가하는 전형적인 풍화 양상을 보여주며, 광물의 풍화작용은 산성환경과 양호한 배수환경과 같은 지역적인 조건에 영향을 받아 복잡하고 다양한 풍화광물을 형성하였다.